PLANKTON OF THE GULF OF MAINE 
425 
B. April 9, 1920, station 20093. 61 
Diatoms very abundant. 
♦Chsetoceras decipiens dominant. 
*Thalassiosira nordenskioldi dominant. 
♦Chaetoceras debile abundant. 
♦Rhizosolenia semispina abundant. 
*Biddulphia aurita. 
*Chsetoceras atlanticum. 
*Ch. contortum. 
*Ch. criophilum. 
*Ch. diadema. 
*Ch. furcellatum. 
♦Ch. scolopendra. 
*Ch. sociale. 
*Ch. teres. 
*Ch. willei. 
*Coscinodiscus asteromphalus. 
*C. concinnus. 
*Pleurosigma stuxbergii. 
*Rhizosolenia setigera. 
♦Thalassiosira gravida. 
♦Thalassiothrix nitschioides. 
3. — Off Cape 
A. March 4, 1920, station 20059 82 (fig. 119): 
Diatoms abundant. 
*Thalassiosira nordenskioldi dominant. 
♦Chaetoceras contortum abundant. 
C. Nearer the coast, in Ipswich Bay, April 9, 
1920, station 20092: 
♦Chaetoceras contortum dominant. 
*Ch. debile dominant. 
*Thalassiosira gravida dominant. 
*Biddulphia aurita. 
♦Chaetoceras atlanticum S. 
Ch. contortum. 
*Ch. decipiens. 
*Ch. diadema. 
*Ch. furcellatum. 
♦Ch. laciniosum. 
♦Ch. teres. 
*Ch. wighami. 
*Coscinodiscus concinnus. 
♦Rhizosolenia semispina. 
*R. setigera. 
Thalassiosira nordenskioldi. 
♦Thalassiothrix nitschioides. 
Elizabeth 
B. April 10, 1920 — Continued. 
*Ch. contortum dominant. 
* Thalassiosira nordenskioldi dominant. 
Biddulphia aurita. 
Chaetoceras debile. 
*Ch. decipiens. 
*Ch. diadema. 
Ch. didymum. 
Ch. sociale. 
Ch. teres. 
Ch. sp. ? 
*Coscinodiscus curvulatus. 
*C. excentricus. 
*Ditylium brightwellii. S. 
Lauderia glacialis 
♦Pleurosigma stuxbergii S. 
*Rhizosolenia setigera. 
*R. semispina. 
Skeletonema costatum. 
Thalassiothrix nitschioides. 
♦Thalassiosira gravida. 
B. April 10, 1920, station 20095: 
Diatoms very abundant. 
♦Chaetoceras debile dominant. 
Biddulphia aurita. 
♦Cerataulina bergonii S. 
♦Chaetoceras atlanticum. 
♦Ch. decipiens. 
♦Ch. diadema. 
Ch. didymum. 
♦Ch. laciniosum. 
♦Ch. scolopendra S. 
♦Ch. sociale. 
♦Ch. teres. 
♦Ch. willei. 
♦Coscinodiscus asteromphalus, 
Coscinosira polychorda. 
♦Eunotia areus S (accidentally present). 
♦Nitschia closterium. 
*N. seriata. 
♦Rhizosolenia semispina. 
*R. setigera. 
♦Skeletonema costatum. 
♦Thalassiosira gravida. 
♦Thalassiothrix nitschioides. 
*i The list for Platts Bank the next day (station 20094) was the same, 'except that it included 'Chxtoceras densum and Ch, 
didymum, * Coscinodiscus curvulatus, * Nitschia seriata, and Skeletonema costatum, but lacked Chxtoceras furcellatum, Ch. willei, and 
Thalassiothrix nitschioides. 
* J The list was the same near Seguin Island on that day (station 20058, fig. 117), except that it lacked Chxtoceras diadema, Coscino- 
discus excentricus, and Rhizosolenia semispina, but included * Chxtoceras atlanticum, * Ch. criophilum, * Ch. laciniosum, * Ch. willei, 
• Coscinodiscus asteromphalus, * C. concinnus, and C. subtilis. 
